JPS5817536B2 - Epoxy resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an epoxy resin composition, which exhibits excellent storage stability, particularly at room temperature, and rapidly progresses the curing reaction at temperatures above about 100"C. The present invention relates to an epoxy resin composition that becomes a cured product.

When curing an epoxy resin, for example, (A) a curing agent such as a polyamine, acid anhydride or phenol, or (B) a curing catalyst such as a BF3 complex or a tertiary amine compound is added to the epoxy resin. This is what is normally done.

However, in case (A), when a polyamine is used, there is the disadvantage that the composition cannot be stored for a long period of time due to its strong reactivity with the epoxy resin, and when an acid anhydride is used, it requires high temperatures for curing. The disadvantage is that it requires long heating times.

On the other hand, in case (B), when a BF3 complex is used, curing is possible at a relatively low temperature, but there is a drawback that the electrical and mechanical properties of the cured resin at high temperatures are poor.

Further, when a tertiary amine is used, a high temperature is required for the curing reaction, and there are also operational problems such as skin irritation.

Furthermore, when curing epoxy resins, attempts have been made to add and blend metal chelate compounds as latent curing catalysts.

However, in this case, not only a high temperature of 200°C or more is required for the curing reaction, but also the amount of the metal chelate compound added is relatively large at about 5%, and good properties are not achieved due to poor dissolution and dispersibility. There is a disadvantage that it is difficult to form a cured resin layer.

Furthermore, compositions in which an organic boron compound or an organic titanium compound is added to an epoxy resin-organosilicone compound system having a silanol group are also known.

However, in these cases, the electrical properties after curing are poor and the storage stability is poor, so that they cannot be said to be practically satisfactory.

The inventors of the present invention proceeded with studies to address these points, and as a result, we discovered that latent curing of organosilanes or organopolysiloxanes having a hydroxyl group bonded to Si in the molecule and a metal compound having an organic group. When added to an epoxy resin as a catalyst, it exhibits excellent storage stability at room temperature, but when heated to about 100°C or higher, it easily undergoes a curing reaction, resulting in a cured resin layer with good electrical and mechanical properties. was found to be obtained.

Based on the above findings, the present invention aims to provide an epoxy resin composition that is easy to handle and suitable for insulation treatment of electrical equipment.

To explain the present invention in detail below, the present invention provides (a) an organsilane or organopolysiloxane having a small amount (both 1 and 1 hydroxyl group bonded to Si) in the molecule of 0.01 to 5% by weight based on the epoxy resin; At least one of the compounds and (b) 0 for the epoxy resin.
．． 001 to 5% by weight of V, AI, or Fe as a central atom, and a chelate compound having a β-diketone compound or an O-ketophenol compound as a ligand is added to the epoxy resin as a latent curing catalyst. This is an epoxy resin composition.

In the present invention, the organosilane or polysiloxane compound having a hydroxyl group bonded to Si, which is a component of the latent curing catalyst for the epoxy resin, includes the following.

That is, the general formula (wherein R and R' may be the same type of alkyl group, phenyl group, aralkyl group, vinyl group, or allyl group, and q and r are positive integers from O to 3, and q is within 3) or an organosilane represented by the general formula % formula % alkali group or a hydrolyzable group, S, t,
, y is a positive integer of O to 2, s + t and X + y are each within 2, u and w are positive integers of 0 to 2, a and b are O or a positive integer of 1 or more, respectively), This is an organosiloxane compound represented by

However, the above organosilane and organopolysiloxane compounds may be used alone or in a mixed system of two or more, and the amount added is 0.01 to 0.01 to
A range of 5% by weight is preferred.

The metal chelate compound constituting another component of the latent curing catalyst for the epoxy resin used in the present invention has a central atom of vanadium, iron, or aluminum, and is a β-diketone type compound or an O-ketophenol type compound. It is a chelate compound that has as a ligand.

The β-diketone type compound used in the present invention is a compound having the following chemical formulas (1), (2) and (3).

(In the formula, R represents an alkyl group or a rogen-substituted alkyl group.

) Specifically, examples of the compound (1) include acetylacetone, trifluoroacetylacetone, pentafluoroacetylacetone, etc., examples of the compound (2) include ethylacetoacetate, and examples of the compound (3) include: Examples include diethyl malonate.

Further, the 0-ketophenol type compound used in the present invention is a compound represented by the following chemical formula (4).

(In the formula, R represents a hydrogen atom, an alkyl group, a halogen-substituted alkyl group, or an alkoxy group.

) Specific examples include salicylaldehyde, ethyl-〇-hydroxyphenyl ketone, and the like.

These compounds exhibit catalytic activity by the ketone in the skeleton forming a chelate bond with the above metal element, and changes in the parts other than the chelate bond forming part of the above compounds may have a slight effect on the degree of catalytic activity. Although it does have an effect, it is not enough to cause loss of catalytic ability.

Generally speaking, in the above compound group, O of formula (4)
- Ketone phenol type compounds have the highest catalytic activity, followed by β-keto ester type compounds of formula (2) and formula (4).
Although the activity tends to decrease in the order of the β-diester type compound of formula (1) and the β-diketone type compound of formula (1), both are usable in the present invention.

Examples of the chelate compounds used in the present invention include tris(acetylacetonato)aluminum, tris(
tris(pentafluoroacetylacetonate)aluminum, tris(salicylaldehydeto)aluminum and tris(dief/L/malonato)aluminum, and in addition, aluminum in these compounds is replaced with iron or vanadium Examples include chelate compounds.

Furthermore, in the present invention, all the bonds of the metal atom do not need to be bonded to ligands, and may be bonded to (1) to two alkoxy groups, phenoxy groups, or acyloxy groups.

When such a group is substituted, the chelate compound becomes even more active.

These chelate compounds may be used alone or in a mixed system of two or more, and the amount added may be about 0.001 to 1% by weight based on the epoxy resin.

The epoxy resin that is the main component in the present invention is commonly known and is not particularly limited.

For example, bisphenol A type epoxy resin, bisphenol F type epoxy resin, phenol novolak type epoxy resin, alicyclic epoxy resin, conjugate ring epoxy resin such as triglycidyl isocyanate and pidantoin epoxy, hydrogenated bisphenol A type epoxy resin, Aliphatic epoxy resins such as propylene glycol diglycidyl ether and pentaerythritol polyglycidyl ether, epoxy resins obtained by the reaction of aromatic, aliphatic or alicyclic carboxylic acids with epichlorohydrin, spiro ring-containing epoxy resins, Ortho allyl phenol, glycidyl ether type epoxy resin which is a reaction product of a novolak compound and epichlorohydrin, glycidyl which is a reaction product of a diallylbisphenol compound having an allyl group at the ortho position of each hydroxyl group of bisphenol A and epichlorohydrin Any ether type epoxy resin or the like may be used.

The epoxy resin composition according to the present invention has the advantage that it has good storage stability and is easy to handle because it undergoes a rapid curing reaction at a temperature of about 100 DEG C., for example.

Furthermore, by selecting the type and composition ratio of the epoxy resin, it is not only suitable for so-called solvent-free applications such as casting, impregnation, and molding, but also easily dissolves in low-boiling point solvents such as dioxane and tetrahydrofuran.

Therefore, it can be easily applied to glass cloth, paper, etc., so it can also be used for forming laminates.

Moreover, the cured resin maintains and exhibits excellent heat resistance, mechanical properties, and electrical insulating properties.

The epoxy resin composition according to the present invention includes the above-mentioned epoxy resin - organosilane or organopolysiloxane.
The organic metal chelate compound may be used alone, or an inorganic photochromic agent or the like may be appropriately added to obtain the same effect.

Example 1 Polymethylphenylsiloxane compound 5H60' having a silanol group (35i-OH group) in 100 parts by weight of epoxy resin Epicor 828 (manufactured by Shell Chemical Co., Ltd., trade name)
18 (manufactured by Toshi Silicone Co., Ltd., trade name) and 1 part by weight of aluminum acetylacetonate were heated and dissolved.
When stored at room temperature, almost no increase in viscosity was observed even after 3 months.

When this composition was heated at 100°C, 15
At 0°C, gelation occurred in 10 minutes.

When this composition was heated at 120° C. for 2 hours and further at 150° C. for 5 hours, it became a light orange transparent and tough cured product.

The properties of this cured product are shown in Attached Table 1.

(Heat distortion temperature is ASTM684 (a), volume resistivity, dielectric loss tangent is JIS K-6911, bending strength is J
Measured according to ISK-7203.

(Similarly below) Example 2 100 parts by weight of epoxy resin Chissonox 221 (manufactured by Chisso Corporation, trade name), 1 part by weight of 5H60180, and 0.1 part by weight of aluminum acetylacetonate were dissolved by heating and stored at room temperature. 3 months elapsed. After that, almost no increase in viscosity was observed.

When this composition was heated at 100°C, 12
At 0°C, gelation occurred in 4 minutes.

When this composition was heated at 100°C for 2 hours and further at 150°C for 5 hours, a tough cured product was obtained.

Table 1 shows various properties of this cured product.

Example 3 100 parts by weight of epoxy resin Epiclon 830 (manufactured by Inu Nippon Ink Chemical Co., Ltd., trade name) was heated to dissolve 1 part by weight of S, H60181, and 0.4 part by weight of aluminum acetylacetate, and stored at room temperature. However, almost no increase in viscosity was observed even after 3 months had passed.

When this composition was heated at 100°C, 15
At 0°C, gelation occurred in 12 minutes.

When this composition was heated at 120°C for 2 hours and further at 150°C for 5 hours, a tough cured product was obtained.

Table 1 shows various properties of this cured product.

Comparative Example 1 After heating and dissolving 3 parts by weight of boron trifluoride monoethylamine complex in 100 parts by weight of Epicor) 828, 2 parts by weight at 100°C.
A cured product is obtained by further heating at 150° C. for 5 hours.

Table 1 shows various properties of this cured product.

Comparative Example 2 A cured product is obtained by dissolving 10 parts by weight of an imidazole compound 2PH2-CN (manufactured by Shikoku Kasei Co., Ltd., trade name) in 100 parts by weight of Epikote 828 and heating the solution at 100°C for 2 hours and further at 150°C for 4 hours.

Table 1 shows various properties of this cured product.

Example 4 100 parts by weight of Epicoat 828, 182 parts by weight of 5H60 and 1 part by weight of iron acetylacetonate were heated and dissolved,
When stored at room temperature, almost no increase in viscosity was observed even after 3 months.

When this composition was heated at 100°C, 15
At 0°C, gelation occurred in 12 minutes.

This composition was heated at 120°C for 2 hours and then at 150°C for 5 hours:
When heated for a while, a pale yellow, transparent and tough cured product was obtained.

Example 6.7 A resin composition having the composition shown in the table below was prepared.

When these compositions were heated at 160° C. for 10 hours, a cured resin product was obtained.

The properties of this cured product are also shown in the same table.

Example 8 A curing catalyst consisting of 3 parts by weight of diphenyldihydroxysilane and 2 parts by weight of the chelate compound shown in the table below was blended with 100 parts by weight of Epicoat 828 to prepare a resin composition.

All of these compositions showed almost no increase in viscosity even after being stored for two months in a dark room at room temperature.

Furthermore, when the gelation time of these resin compositions was measured, the results were as shown in the same table.

Example 9 Epoxy resin Shodine 540 (product name, Showa Denko)
400 parts by weight, Epicote 1001 (trade name, Shell) 800 parts by weight, Epicote 152 (trade name, Shell) 1500 parts by weight, polysiloxane compound 5H-601
8 (trade name, Toshi Silicone Co., Ltd.) 100 parts by weight, 80 parts by weight
55 dissolved in methyl ethyl ketone at a temperature of ~100°C.
A wt% solution was prepared.

Add aluminum Uno triethyl acetoacetate 2 to the above solution.
．． Polysiloxane compound TS with 6 parts by weight and hydroxyl group
2.6 parts by weight of R-160 (trade name, Toshiba Silicone Co., Ltd.) was added and blended.

This resin solution was impregnated and applied to a plain woven glass cloth treated with epoxy silane, air-dried, and then dried at IOO° C. for 10 to 30 minutes to obtain a prepreg with a resin adhesion of about 45%.

A piece of 200 x 200 mm was cut out from the prepreg thus obtained, 8 of the cut pieces were stacked on top of each other, and heated at 180°C for 30 minutes.
After heating and pressure molding for 1 minute, actuator curing was performed at 180° C. for 5 hours to produce a laminate.

A test piece was cut out from this laminate and the weight loss after heating at 200 DEG C. for 100 hours was measured to be 11%, and the electrical insulation properties after heating for 200 to 1000 hours were as shown in Table 2.

Example 10 Epoxy resin Chissonox 221 (trade name Chisso Co., Ltd.)
100 parts by weight, epoxy resin ECN1299 (trade name,
Ciba Geigy) 200 parts by weight, polysiloxane 5H-
6018 (trade name, Toshi Silicone Co., Ltd.) 3 parts by weight to 50
It was uniformly dissolved in methyl ethyl ketone at ~60 to 60°C to prepare a resin content of 50% by weight.

While stirring, 0.3 parts by weight of aluminum triethyl acetoacetate and 40 parts by weight of natural graphite having an average particle size of 5.5 μm were gradually added to 120 parts by weight of the above resin solution to obtain a molding composition. After removing the solvent under reduced pressure, the mold temperature was 180℃ and the pressure was 180kg/c.
A molded plate was obtained by performing heat and pressure molding on the shoulder for 7 minutes.

This molded plate was after-cured at 200°C and subjected to a friction and wear testing machine (Model E F M -n-B, Toyo Baldwin Co., Ltd.).
When the friction coefficient was measured under a load of 1.00 kg, it was μ-0.23, the exothermic temperature was 165° C., and the PV value was 4100.

Example 11 Alicyclic epoxy resin Chinsonox 221 (trade name, Chisso Corporation) 50 parts by weight, Showa Denko K.K.) 50 parts by weight, polysiloxane compound 5H-6018 (trade name,
Toshi Silicone Co., Ltd.) o, o5 parts by weight, aluminum triacetylacetonate 0.3 parts by weight and particle size 200
A casting resin composition was prepared by stirring and mixing 180 parts by weight of mesh silica powder.

On the other hand, a coil element is made by winding a flat rectangular copper wire into a disk shape with aromatic polyamide non-woven fabric Nomex (trade name, DuPont) tape wound twice with 1/2 overlap, and an aromatic polyamide non-woven fabric is placed between each stage. A coil was constructed by stacking the inserts in five stages and wrapping the outer periphery with coarse glass tape twice in a 1/2 overlap.

Place the above coil in a casting mold and put it in a vacuum impregnation tank 1
After reducing the pressure to 77,177 LHg, the resin composition for casting (heat source at 80 to 110°C) was poured into a casting mold and pressurized at a gauge pressure of 5 kg/crA for 5 hours to cast a coil.

After this casting, the coil was taken out from the tank and heated and embedded sequentially at 15Q°C for 5 hours and at 170°C for 10 hours to harden the resin and obtain a cast coil.

155°C to -40°C for the cast coil thus obtained.
When a heat cycle test was conducted using electrical heating and cooling within a range of 0.05 to 10.00, no cracks were observed in the cast resin layer, and good results were obtained.

It also showed good performance in heat shock tests conducted between 80°C and 10°C, and had highly reliable functionality when assembled into a dry transformer.

Example 12 Bisphenol A type epoxy resin Epicoat 1001
(Product name, Shell Chemical Co., Ltd.) 40 parts by weight, Novolac type epoxy resin Epicor) 152 (Product name, Shell Chemical Co., Ltd.)
60 parts by weight and polysiloxane compound 5H-6018
(Product name, Tol/・Silicone Co., Ltd.) 2.0 parts by weight 60
Dissolved in methyl ethyl ketone at a temperature of ~70 °C,
% solution by weight.

Add aluminum triethyl acetoacetate 2 to this solution.
．． 6 parts by weight, polysiloxane compound TSR with hydroxyl group
2.6 parts by weight of -160 (trade name, Toshiba Silicone Co., Ltd.) were added and uniformly dissolved and mixed.

This resin solution was impregnated and applied to a hard fired type laminated mica sheet with a thickness of about 0.1 mm lined with 35 μm coarse glass cloth, and dried at 60 to 70°C for 5 to 20 minutes to form an adhesive. A Bripreg Yaika sheet of about 45% was obtained.

This prepreg mica sheet was further cut into 30 mm width pieces using a slitter to obtain a tape.

This mica tape had a shelf life of over 3 months at room temperature.

Next, the prepreg mica tape was wound 5 times with 1/2 winding around a wire ring, and then it was wrapped with a press or molding machine at 25kg/ct.
Mold at 150° C. for 1-2 hours while applying ft of pressure.

Thereafter, it is heated and cured for about 10 hours in a 160'c open chamber to obtain an electrically insulating coil.

The electrically insulated wire ring obtained in this way was
High dielectric breakdown strength over 0/7n and 15kg/m
It exhibited a higher bending strength of 4 or higher than conventional silicone mica insulation.

In addition, despite curing at a relatively low temperature and in a short time,
tan δ (dielectric loss tangent) at IK'J/ynm is also 1
Within 0%, electrical loss at high temperatures was small.

Furthermore, after heating this electrically insulated coil at 200° C. for 1000 hours, the dielectric breakdown voltage and bending strength were tested, and there was no significant increase in tan δ in IKV/mm, which was almost unchanged from the initial value.

After the dielectric breakdown, the insulating layer was disassembled and visually observed, but no peeling of the insulating layer or carbonization of the resin was observed.
It turned out to be an electrically insulated coil with extremely high heat resistance and excellent mechanical properties.

As is clear from the above examples, the resin composition of the present invention is suitable for impregnation and casting, and is also soluble in organic solvents with a low boiling point and not strong polarity, so it can be used for laminates, molding materials, prepregs, and bind tapes. It can be said that it is suitable as an insulating material for electrical equipment such as wedges, bearing materials, etc.

Claims (1)

[Claims] 1(a) 0.01 to 5% by weight of 1 based on the epoxy resin
At least one organosilane or organosiloxane compound having at least one hydroxyl group bonded to Si in the molecule; and (b) 0.001 to 5% by weight based on the epoxy resin.
It is characterized in that a chelate compound having V, AI or Fe as a central atom, and a β-diketone compound and a chelate compound having an O-ketophenol compound as a ligand is added to the epoxy resin as a latent curing catalyst. Epoxy resin composition.